title: Immunogenicity, safety, and lot consistency of a novel inactivated enterovirus 71 vaccine in Chinese children aged 6 to 59 months.
abstract: The determination of lot-to-lot consistency in the manufacturing process is a mandatory step in the clinical development of the novel enterovirus 71 (EV71) vaccine. A phase III, randomized, placebo-controlled, double-blind trial assessed the lot consistency, immunogenicity, and safety of the EV71 vaccine in children aged 6 to 59 months. Healthy children (n = 1,400) received one of three lots of the EV71 vaccine containing 400 U of EV71 antigen or a placebo at days 0 and 28. Blood samples were collected before dose 1 and at 28 days after dose 2 (day 56) for an anti-EV71 neutralizing antibody (NTAb) assay. The geometric mean titer (GMT) and the seropositivity rates (with titers of ≥1:8) were compared at day 56. After each dose, the solicited injection site and general adverse events (AEs) were recorded for 7 days, and unsolicited AEs were recorded for 28 days. At day 56, the seropositivity rates ranged from 99.7% to 100% for the vaccine groups. The NTAb GMTs for the vaccine were 140.3 (95% confidence interval [CI], 117.8 to 167.1), 141.5 (95% CI, 118.0 to 169.6), and 146.6 (95% CI, 122.5 to 175.3). The two-sided 95% CI of the log difference in GMTs between the pairs of lots were between -0.176 and 0.176, therefore meeting the predefined equivalence criteria. The percentages of subjects reporting any injection site AEs, general AEs, or serious AEs were similar across the four vaccination groups. In conclusion, the demonstration of consistency between the manufacturing lots confirms for the purposes of clinical development the reliability of the EV71 vaccine production process. (This study has been registered at ClinicalTrials.gov under registration no. NCT01636245.).
authors.affiliation: Jiang-Su Provincial Center for Disease Control and Prevention, Nanjing, China.
authors.forename: Yue-Mei
authors.initials: YM
authors.lastname: Hu
authors.forename: Xu
authors.initials: X
authors.lastname: Wang
authors.forename: Jun-Zhi
authors.initials: JZ
authors.lastname: Wang
authors.forename: Ling
authors.initials: L
authors.lastname: Wang
authors.forename: Yong-Jie
authors.initials: YJ
authors.lastname: Zhang
authors.forename: Lin
authors.initials: L
authors.lastname: Chang
authors.forename: Zheng-Lun
authors.initials: ZL
authors.lastname: Liang
authors.forename: Jie-Lai
authors.initials: JL
authors.lastname: Xia
authors.forename: Qi-Gang
authors.initials: QG
authors.lastname: Dai
authors.forename: Ya-Ling
authors.initials: YL
authors.lastname: Hu
authors.forename: Qun-Ying
authors.initials: QY
authors.lastname: Mao
authors.forename: Feng-Cai
authors.initials: FC
authors.lastname: Zhu
authors.forename: Yu-Fei
authors.initials: YF
authors.lastname: Song
authors.forename: Fan
authors.initials: F
authors.lastname: Gao
authors.forename: Jiang-Ting
authors.initials: JT
authors.lastname: Chen
mesh_terms: D057134:Antibodies, Neutralizing / Q000097:blood*; D000914:Antibodies, Viral / Q000097:blood*; D002675:Child, Preschool; D002681:China; D004311:Double-Blind Method; D029821:Enterovirus A, Human / Q000276:immunology*; D004769:Enterovirus Infections / Q000276:immunology / Q000517:prevention & control*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D010919:Placebos; D014611:Vaccination / Q000009:adverse effects; D015164:Vaccines, Inactivated / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology; D014765:Viral Vaccines / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology*
chemical_list: D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D010919:Placebos; D015164:Vaccines, Inactivated; D014765:Viral Vaccines